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Wireless Networking Hardware Technology

Wireless Internet Access Uses Visible Light, Not Radio Waves 264

An anonymous reader writes to tell us that a company has demonstrated a new form of wireless communication that uses light instead of radio waves. "Its inventor, St. Cloud resident John Pederson, says visible-light embedded wireless data communication is the next step in the evolution of wireless communications, one that will expand the possibilities in phone and computer use. The connection provides Web access with almost no wiring, better security and with speeds more than eight times faster than cable."
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Wireless Internet Access Uses Visible Light, Not Radio Waves

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  • light hax (Score:4, Funny)

    by Anonymous Coward on Friday January 16, 2009 @06:10PM (#26489335)

    im in ur bawx stealin ur photons

    • by Anonymous Coward

      "Because light does not travel through walls, cell phones and government and banking information would be more secure."

      It's not a bug, it's a feature, really - it is, please believe me.

      • by Tubal-Cain ( 1289912 ) * on Friday January 16, 2009 @08:53PM (#26491733) Journal
        So using visible light negates the need for expensively embedding faraday cages into the buildings.
      • by hairyfeet ( 841228 ) <bassbeast1968@gm[ ].com ['ail' in gap]> on Friday January 16, 2009 @10:50PM (#26492741) Journal

        So I'm going to lose connection every time someone stands in between me and the light emitter? And cell phones? So every time somebody walks past me while I'm on the phone I lose the signal?

        We are already coming up with new ways to make fiber cheaper and with this stuff you'd still need fiber because you aren't going to get great distances with it. Not to mention the billions it would take to install this thing along the roadways so it could work as a cell phone. Maybe in small indoor areas it might be decent, but if I am in a small area there is already gigabit and fiber. So to me this seems like a solution with more problems than the tech they want to replace. No thanks.

        • Re: (Score:3, Interesting)

          by shadow349 ( 1034412 )

          So I'm going to lose connection every time someone stands in between me and the light emitter?

          I didn't RTFA, but if the system were based on diffuse, ambient light in the room, then that shouldn't be a problem.

          I swear that I remember a similar idea from around 10 years ago where they wanted to use fluorescent lights in much the same way ... switch them on and off thousands of times per second and you could use them as a data channel if your device had an optical sensor. By setting the hi and low thresholds

      • Re: (Score:3, Interesting)

        by Cramer ( 69040 )

        Well now, that depends on both the wall and the light source. No one has said what wavelength of light is being used, at what power, and what frequency/modulation. While I'm sure his setup goes well beyond IRDA, using LEDs ("light") for data transmissions has been around for over 20 years. Both my cellphone and laptop have IR ports on them -- even used it for internet access once. (laptop doesn't have bluetooth and I don't have the 150$ (f*** you Ericson) USB cable for the phone.)

        [Back in college, eons a

  • But... (Score:3, Informative)

    by goto begin ( 1338561 ) on Friday January 16, 2009 @06:11PM (#26489345)
    Radio waves are part of the light spectrum?
  • ... are light, you insensitive clod!

    • Next step?? (Score:5, Insightful)

      by PsyciatricHelp ( 951182 ) on Friday January 16, 2009 @06:14PM (#26489431)
      Last time I checked light doesn't travel through my wall. Radio waves do.
      • Re:Next step?? (Score:4, Informative)

        by DragonWriter ( 970822 ) on Friday January 16, 2009 @06:19PM (#26489539)

        Last time I checked light doesn't travel through my wall.

        Visible light doesn't, probably. But "light" is a term that can be used to refer to the whole of the EM spectrum.

        • Re: (Score:3, Informative)

          So if you ask someone to "turn on the light," what are you referring to? The radio? ;)

          When pitting "light" against "radio" waves, the implication seems to be plain that he's talking about visible light.

          • Your radio receiver doesn't emit EM radiation. Your lightbulb does.
            • Since we're in a pedantry fight, I have to interject that pretty much every electrical device emits EM radiation, just not necessarily intentionally or productively. Usually between the FCC and the UL these emissions are kept out of a range that would cause undue interference with other devices (they also have to take the interference from other devices within reasonable ranges without blowing up in an inductive current hissy fit), but that depends also on their application and how much shielding is used.
        • but the article is about transmission with visible light and this discussion has already been had in the thread above.

          so quit being pedantic and either tell us why this is better or admit that it's worse

        • Visible light doesn't, probably. But "light" is a term that can be used to refer to the whole of the EM spectrum.

          Wow. I wish I was so smart that I found the use of that term confusing.

      • Re:Next step?? (Score:5, Interesting)

        by snowraver1 ( 1052510 ) on Friday January 16, 2009 @06:34PM (#26489853)
        I read an article about this or similar technology several months ago. Sure, light doesn't do through walls, but that could be an advantage. You could setup a wireless network that asctually stops at the building perimiter.

        The other article (not sure if this one does didn't read it) indicated that this technology could be incorporated into LED lighting. Basically your overhead lighting would become the access point. There would be recievers in the room as well that would pick up your transmissions and presumably put them on some sort of physical media (cat6, fibre). Pretty neat, but to me sound extremely finicky.

        -- Snow.
    • by LilGuy ( 150110 )

      Well they certainly aren't very heavy...

  • Warning! (Score:5, Funny)

    by Fjandr ( 66656 ) on Friday January 16, 2009 @06:12PM (#26489371) Homepage Journal

    Looking at the access point can cause severe retinal burns. We are not responsible for retinal damage or permanent blindness as a result of using our product. Thank you, and have a nice day.

    • Re:Warning! (Score:5, Funny)

      by zappepcs ( 820751 ) on Friday January 16, 2009 @06:20PM (#26489565) Journal

      Yeah, but retinal damage only occurs when using P2P protocols to share pr0n according to this flashy brochure the preacher man gave me.

    • Re: (Score:3, Funny)

      by orclevegam ( 940336 )
      Please be advised that person prone to seizures should not be in the same room as the access point as the natural oscillations in the carrier wave have been shown to cause seizures.
    • In the first trial network installation in Birmingham, Alabama, 665 small Japanese children fell to the floor in convulsions.
  • WARNING! (Score:5, Funny)

    by LiquidCoooled ( 634315 ) on Friday January 16, 2009 @06:12PM (#26489373) Homepage Journal

    Do not look at the internet with your remaining eye.

    • Re:WARNING! (Score:5, Funny)

      by Anonymous Coward on Friday January 16, 2009 @06:15PM (#26489455)
      I got that warning after my first goatse encounter. I've been really cautious since.
  • huh? (Score:3, Funny)

    by Lord Ender ( 156273 ) on Friday January 16, 2009 @06:12PM (#26489389) Homepage

    Radio is just another color of light--a very, uh, extremely red color.

    • Re:huh? (Score:5, Insightful)

      by nine-times ( 778537 ) <nine.times@gmail.com> on Friday January 16, 2009 @06:48PM (#26490113) Homepage

      Yes, it seems like they're drawing a couple suspect distinctions in this article. They talk about "light" as being very different from "radio" even though they're both EM radiation, and they talk about "using light" as very different from "using fiber optics", even though it's really just a difference of medium.

      I don't really see it working out. We already use that portion of the EM spectrum for... you know... seeing. I guess you could claim that being easily blocked (e.g. by walls) is an advantage, but for most people in most circumstances, being able to pass through lots of materials would be a greater advantage. If you really want tighter security, then instead of relying on walls to block the signal, this technology could be improved by creating some sort of conduit that would go directly from one point to another. Like some kind of fibrous, wiry, cable-like structure between them. I'm sure that would be much better than fiber optics.

      • They talk about "light" as being very different from "radio" even though they're both EM radiation, and they talk about "using light" as very different from "using fiber optics", even though it's really just a difference of medium.

        Technically, you are correct that light is light (be it radio or visible or ultraviolet or whatever) and that, at least in the simplest terms, the only difference between fiber optics and open air light communication. However, the technical difficulties involved in using visible light in communication vs radio waves are incredible. Nobody has done it before and the reason is because it is HARD.

        The very reason fiber optics exist is to overcome the challenges of using visible light as communication. Becaus

  • by eobanb ( 823187 ) on Friday January 16, 2009 @06:12PM (#26489405) Homepage
    It's called free space optics. The technology has been around a long time, in fact, and for a while it was fairly common on laptops. It was called IrDA, and though it was fairly short range you could use it to transfer files, establish a TCP/IP connection, etc.

    I remember playing a Starcraft game with an iMac G3 and PowerBook G3. A friend and I used AppleTalk over IrDA. Unfortunately it was rather awkward since they had to line up, but we figured out you could bounce the infrared beam with mirrors. So we didn't need ethernet, we could play wirelessly...this was in 1998, long before 802.11b became mass-market.
    • From TFA:

      The technology could be exciting for cell phone users as well. Cells phones use radio waves that can travel through walls and be intercepted. That means they cannot be used for sensitive conversations, such as those involving national security or banking transactions.

      Light does not travel through walls and the LVX could offer a more secure conversation, Pederson said. He said cell phones already have the technology needed to adapt to LVX. He is looking for a cell phone manufacturer to develop a pho

    • by Chabo ( 880571 )
      Most PDAs at the time (like when Palm was in its big heyday) supported IrDA too.
    • Had you been thinking, you could have sold IrDA switches in the form of a box of mirrors. Or IrDA hubs in the form of disco balls.
    • by should_be_linear ( 779431 ) on Friday January 16, 2009 @07:08PM (#26490485)

      And here is GPL'd design: http://ronja.twibright.com/ [twibright.com]

  • Means little, when the current cable speeds can basically be infinite. You know how you have all those TV channels traveling through the same wire? They can do the same with the internet communications as well-- just use multiple channels in parallel.

    8-channel cable DOCSIS spec [wikipedia.org]

    Or maybe they aren't talking about cable-internet specifically; I only skimmed TA :)

    • Re: (Score:3, Informative)

      by Chabo ( 880571 )
      They didn't mention speeds at all in the article, but on at least one occasion when he used the word "cable", he meant fiber-optics:

      If it works out as Pederson plans, his project would replace the need for fiber optic wires that run underground and in buildings. The cost savings alone in construction and wiring make it impressive, St. Cloud Mayor Dave Kleis said.

      âoeRight now, we are going through a tremendous amount of fiber optics. If this can move and transmit with light rather than cable, there is significant savings in that alone,â Kleis said.

      Now, given that they're essentially the same technology, I can't see how this would be faster than fiber. But if by "cable" when talking about speeds, he does mean DOCSIS, then that's easy. 10 Gigabit ethernet is already more than 20 times faster than EuroDOCSIS 3.0, 8-channel, and most varieties of 10GbE run over fiber.

  • oldnews (Score:4, Informative)

    by rpp3po ( 641313 ) on Friday January 16, 2009 @06:13PM (#26489423)
    For how many decades does my university use laser links to our dorms? For how many decades do we have infra red data transmission, e.g. in remote controls?
  • Light, huh. (Score:3, Insightful)

    by girlintraining ( 1395911 ) on Friday January 16, 2009 @06:14PM (#26489435)

    Has this guy never seen snow? Or fog? Or rain? Does he live in a desert? Two words: Atmospheric absorption.

    • by Xtravar ( 725372 )

      Two words: error correction!


    • Considering that St. Cloud is in Minnesota, it is very likely he has seen all of those things.

      This product would be tailored to applications inside buildings, where those things don't happen too frequently. This technology is perfect for security type applications.

      • Or they could *gasp* run a fscking cable and not worry about a glorified IR link. Once you've gone to something like IR you're already dealing with a limited area so mobility isn't really a prime factor (ok, yeah, you could string a whole sequence of these along the roof and work out some system to migrate from one to another as the person walks around the building, but that's not exactly practical), and there's still a chance that someone could eavesdrop on the network by say strategically placing a mirror
    • Thermal weapon sights and FLIR systems see thru fog, rain, and snow quite well. If the wavelength is smaller than the particle it's going around, you don't see it.

      All media have distortion and absorption problem, it's up to the protocol layers to deal with that. The mufuckin microwave slows your 802.11 throughput...

  • by SWPadnos ( 191329 ) on Friday January 16, 2009 @06:19PM (#26489555)

    Tinfoil glasses :)

  • Didn't we already go through this idea a couple times? Even to the point of HP(?) having incredibly ridiculous multi-emitter bulbs for computer lab installs and things?
  • There's a reason we don't already use visible light signals to send wireless data (except if we're lost in the wilderness, I guess). It's VISIBLE. Can you image how annoying it would be to have light flickering around you all the time from your communicating devices? One of the primary advantages of the various bands we use (radio, infrared, etc.) is that they don't interfere with our normal operations: they're invisible.

    We've got plenty of bandwidth that doesn't interact directly with the human body. Why d

    • by CaptainPatent ( 1087643 ) on Friday January 16, 2009 @06:39PM (#26489939) Journal

      Can you image how annoying it would be to have light flickering around you all the time from your communicating devices?

      You know that thing you looked into when you typed your message. Be it a CRT, LCD or Plasma, it flickers at 40-120 times per second.

      Communication applications would flicker even faster to the point you wouldn't notice unless you sent a constant string of 0's or 1's.

      Don't get me wrong, I still think it's a bad idea for line of sight and other interference reasons, but flicker is near the bottom of that list.

      • No, they don't do a true flicker 40-120 times per second, unless you are actually showing alternate frames of black and white. CRT phosphor material glows for a range of time (optimally equal to the reciprocal of the refresh rate). LCDs don't flicker at all, unless you count the dithering of cheap lower-color panels, which isn't much luminance change anyway. I'm not familiar enough with plasma tech to know, but I haven't noticed any flickering on those displays.

        Now, a DLP projector with color wheel IS re

    • by HTH NE1 ( 675604 ) on Friday January 16, 2009 @06:45PM (#26490067)

      Can you image how annoying it would be to have light flickering around you all the time from your communicating devices?

      Oh, cut the bleeding heart crap, will ya? We all have our switches, lights, and knobs to deal with. At this very moment I surrounded by hundreds of thousands of blinking and beeping lights, blinking and beeping and flashing and flashing and I can't take it anymore! They're blinking and beeping and flashing! Why can't anyone stop it? Why doesn't someone pull the plug?!

  • Andy Tanenbaum has a nice story about that. On a conference they wanted to use a modulated laser to beam an internet connection to another building. Except they calibrated the target at night, it tested fine. But during the day the air would warm and break the connection. He found it rather odd they didn't just use a cable the next day, but the management insisted on using the broken technology. Didn't work they entire conference.

  • by Ancient_Hacker ( 751168 ) on Friday January 16, 2009 @06:39PM (#26489945)

    It's been investigated but the technology just won't work out. Light sensors have a strong speed/intensity tradeoff. Even with a several-inch wide lens you can't collect enough light to drive a sensor at more than a few kilobits/sec. And people hate to keep pointing the sensor at the opposite party.

    And if the room has LED or CCFL lighting the interference from those is mighty intense.

    • Free space optic might be a solution to wireless HDMI. Put an LED light in the room and modulate it in the Mhz range. Humans will never notice.

      Of course I've never understood why people want wireless HDMI. You still have to wire power to the monitor.

  • If your house is on fire, the network goes down.

    To paraphrase Sun....The Network is the Smoke Detector.

  • An anonymous reader writes to tell us that a company has demonstrated a ...

    "An marketing drone writes to tell us that his company has demonstrated a ..."

    There, fixed for ya ;)

    • Correction:
      "An marketing drone writes to tell us that his company has demonstrated a ..."

      There, fixed for ya ;)

      "A marketing drone writes to tell us that his company has demonstrated a ..."

      There, fixed for ya ;)

  • My foot, people were doing this decades ago in the analog world.

    If you include fiber.. its digital too.

  • I recall hearing about Ronja [twibright.com] on /. years ago, and they have deployed it for a wireless net.

  • From TFA:

    "If I can take this to the next step, I think think it is going to be good for our country," Pederson said.

    Quite apart from the fact the country isn't explicitly mentioned in TFA (I assume it's the USA), why would someone say this? Not good for humanity, or for the communications or IT industries, but good for a specific country? Strange.

  • by John Sokol ( 109591 ) on Friday January 16, 2009 @07:01PM (#26490347) Homepage Journal

    1.) There is TCP/IP over Infrared (IrDA) and comes standard on Windows and works also in Linux.
      http://web.pdx.edu/~mendyke/ip7780.html [pdx.edu]

    2.) there are many laser link systems out there.
        I even worked on one.
        http://www.dnull.com/zebraresearch/company-mail.html [dnull.com]

    3.) The 802.11 standard also includes the 802.11 Infrared (IR) Physical Layer. 802.11 IR defines 1Mbps and 2Mbps operation by bouncing light off ceilings and walls to provide connectivity within a room or small office. This infrared version of the standard has been available since the initial release of the 802.11 standard in 1997.

    4.) Spectrix Corporation of Mundelein, Illinois had a proprietary solution for this. I think they are out of business now.
    http://books.google.com/books?id=QZrrXcs1R9gC&pg=RA1-PA207&lpg=RA1-PA207&dq=%22Spectrix+Corporation+%22&source=bl&ots=kMxMofcTd7&sig=qd4QvwoREWQloJKwnpmp63j-Z-I&hl=en&sa=X&oi=book_result&resnum=4&ct=result [google.com]

    If you explore the link above from the book "Wireless Computing" By Ira Brodsky Published by John Wiley and Sons, 1997. This book goes in a lot of detail about many IP over optical solutions available at that time.

  • Utter bullshit (Score:5, Insightful)

    by topham ( 32406 ) on Friday January 16, 2009 @07:08PM (#26490483) Homepage

    The article is utter bullshit.

    Using light, as opposed to radio waves is NOT more secure, unless the room has no windows, or others areas for light to escape.
    Wiring a room to support it could easily cost $300 (you still need atleast one network drop to the room, and mount the transmitter).

    Are there environments where the slight advantages it has may be worth it? sure. but they will be so rare that the cost of the device will stay quite high.

    THe article looks like a puff piece designed to lure in investors.

  • I hate stories like this. It suggests that "light" is somehow different than "radio waves". They're the same thing, the difference is that we can see in that portion of the spectrum.

  • by Animats ( 122034 ) on Friday January 16, 2009 @08:02PM (#26491139) Homepage

    1996 called. It wants its HP NetBeamIR Infrared Ethernet Access Point [shopping.com] back.

    IR access points have been around for years, and they work OK. They can even be made to work through diffuse reflections, so you don't have to have a clear line of sight. But you need a lot of access points to cover a space.

  • There's a bigger team at Boston University [bu.edu] that's been working on this technology.

    I particularly like their plans for use in cars. I can imagine combining this with nano piezoelectric [sciencedaily.com] technology to create roadways that use passing car vibrations to power illuminated markings that can also transmit road condition information to passing cars or link their light-based inter-car networks around corners and over hills.

    The future's so bright, I gotta wear shades that decode and display ambient porn...
  • But won't this require prefect line-of-sight to have any hope of working?

    I'm imagining something like a TV remote, or those IRda systems PDAs and printers used to have but, since it's in the visible band of the spectrum, with more line-of-sight problems. I don't see anything like that replacing 2.4GHz wireless any time soon.

  • Light is part of the RF spectrum... just a particular part that the human eye can see. So is heat. We don't use these sections because they're very annoying to humans to have fluctuating seemingly randomly for transfer of data.

Honesty is for the most part less profitable than dishonesty. -- Plato